The purpose of this study is to use a closed-loop Control-to-Range (CTR) system in adolescents with type 1 diabetes in an outpatient setting, and to evaluate the CTR system's ability to significantly improve blood glucose levels when an insulin bolus is omitted for a 30 gram carbohydrate snack and when insulin bolus is insufficient for the amount of carbohydrates consumed for a meal. The primary objective of this study is to use a closed-loop Control-to-Range (CTR) system to significantly reduce the post-prandial blood glucose excursion in adolescents with type 1 diabetes who omit and/or under-bolus insulin for either snacks or meals. Up to 20 subjects aged ≥13 and ≤18 years old will be tested.

The primary objective of this study is to use a closed-loop Control-to-Range (CTR) system to significantly reduce the post-prandial blood glucose excursion in adolescents with type 1 diabetes who omit and/or under-bolus insulin for either snacks or meals.

The purpose of this study is to use a closed-loop Control-to-Range (CTR) system in adolescents with type 1 diabetes in an outpatient setting, and to evaluate the CTR system's ability to significantly improve blood glucose levels when an insulin bolus is omitted for a 30 gram carbohydrate snack and when insulin bolus is insufficient for the amount of carbohydrates consumed for a meal. The CTR system is comprised of two algorithmic layers: (i) A Safety Supervision Module (SSM) which contains a predictive insulin request dampener (or brakes); (ii) a Range Correction Module (RCM), consisting in (a) a Hyperglycemia Mitigation System, and (b) Insulin on Board controller. Both modules will receive continuous glucose monitoring (CGM) and historical insulin delivery data. The SSM will monitor the safety of the subject's continuous subcutaneous insulin infusion pump (CSII) to prevent hypoglycemia. The RCM will be responsible for optimizing blood glucose (BG) control and mitigating postprandial hyperglycemic excursions through a mix of increased basal rate and, potentially, isolated insulin boluses. To run CTR, we will use our wearable artificial pancreas platform, known as DiAs (Diabetes Assistant) which consists of a smart phone running CTR and connected to standard insulin delivery and CGM devices.

Eligibility

Ages Eligible for Study:

13 Years to 18 Years

Genders Eligible for Study:

Both

Accepts Healthy Volunteers:

No

Criteria

Inclusion Criteria:

≥13 and ≤18 years old

Clinical diagnosis of type 1 diabetes mellitus for at least 2 years as noted by the following:

No data at diagnosis is available but the participant has a convincing history of hyperglycemia consistent with diabetes

Criteria for requiring insulin at diagnosis (at least 1 criterion must be met):

Participant required insulin at diagnosis and continually thereafter

Participant did not start insulin at diagnosis but upon investigator review likely needed insulin (significant hyperglycemia that did not respond to oral agents) and did require insulin eventually and used continually

Participant did not start insulin at diagnosis but continued to be hyperglycemic, had positive islet cell antibodies - consistent with Latent Autoimmune Diabetes in Adults (LADA) and did require insulin eventually and used continually

Use of an insulin pump to treat his/her diabetes for at least 6 months

Actively using a carbohydrate (CHO) /insulin ratio for insulin bolus adjustments in order to keep blood glucose in a predefined range

Tanner stage II or greater based on physician exam

HbA1c between <10.5% as measured with DCA2000 or equivalent device

Not currently known to be pregnant, breast feeding, or intending to become pregnant (females)

Demonstration of proper mental status and cognition for the study

Willingness to avoid consumption of acetaminophen-containing products during the study visits involving DexCom use

Self-reported behavior of snacking without insulin coverage or under bolus for meals

Willingness to consume a 30 grams snack without insulin coverage and willingness to bolus 75 % of usual treatment for an 80 grams lunch during both admissions

Willingness to remove home CGM for admissions if the subject typically wears a CGM

Medication stability in the preceding two months if taking antihypertensive, thyroid, anti-depressant or lipid lowering medication

Reported history of missed or inaccurate bolus treatments at meal time

Exclusion Criteria:

Diabetic ketoacidosis (DKA) within the 6 months prior to enrollment

In adherence with the One Touch Ultra 2 User Guide, subjects with hematocrit levels below 30% or above 55% will be excluded. Severe hypoglycemia resulting in seizure or loss of consciousness in the 12 months prior to enrollment

Pregnancy; breast feeding, or intention of becoming pregnant

Uncontrolled arterial hypertension (based on resting blood pressure > 95 percentile as listed according to age and height percentile in the Harriet Lane Handbook of Pediatrics)

Acetaminophen will be restricted 24 hours before the insertion of not be allowed while the continuous glucose monitor. is in use.

Medications that block symptoms of hypoglycemia, including but not limited to beta blockers.

Subjects on amylin analogs will be asked to withhold the medication during the outpatient admissions.

Contacts and Locations

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Please refer to this study by its ClinicalTrials.gov identifier: NCT01890954